This invention relates to compositions for topical application to teeth. More particularly it relates to compositions and methods which substantially reduce the elution of a previously applied therapeutic agent from teeth. The compositions and methods of the invention are especially useful in inhibiting the growth of cariogenic bacteria and preventing the formation of plaque on teeth in an oral environment.
Dental plaque results when cariogenic bacteria (e.g., Streptococcus mutans) collect in colonies and form deposits on tooth surfaces. The presence of the bacteria and deposits is extremely detrimental to the health of the tooth for, if left unchecked, they may result in infected gingival tissue, the formation of dental caries and possibly periodontal disease. In extreme cases their presence may even result in the loss of teeth. Many attempts have been made to control or prevent both the occurrence of dental caries and the formation of dental plaque. For example, fluoride solutions or gels have been used. Treatment with these materials is typically performed in a dental office at periodic, but not frequent, intervals. Such treatments are primarily intended to render tooth enamel more resistant to the acid action caused by plaque. They do not, however, result in plaque control for an extended period since plaque reestablishes itself on the teeth shortly after ingestion of food.
Even when the frequency of application of such solutions and gels is increased only partial control has been shown. For example, studies wherein a fluoride-containing solution (1% fluoride concentration) was applied four to five times in the course of a year have demonstrated that this technique had only limited success due to the rapid reestablishment of plaque in the oral cavity. Moreover, the daily application of a fluoride gel by means of a custom-fitted polyvinyl mouthpiece for a period of twenty-one months also showed no substantial change in plaque formation among treated and untreated patients. See "Clinical Anticaries Effect of A Repeated Sodium Fluoride Application by Mouthpiece," Journal of the American Dental Association, V. 75, No. 3, September, 1967, pages 638-644.
As a result, there has been no truly effective prophylactic treatment for teeth made available. However, the present invention provides such a treatment.